There were three rounds of interviews. Questions were based on coding, understanding/debugging code, OS, networks, and system design.

• Coding round
• Code, OS-based questions, and output of C programs
• Networking, OS, system design, and code debugging

Round 1: Coding The question was based on IP fragmentation, where data length was divided into multiples of MTU (Maximum Transmission Unit). Defragment all received fragments into one packet.

Round 2: Asked to code an array question. Questions were based on the code I had written, tested with multiple cases.

Questions on process memory structure: Stack, heap, etc.

OS-based questions: Threads, multitasking (my code's behavior in a multiprocessor environment), paging, virtual memory, context switching, dispatcher, etc.

Given a C program snippet, predict its output and answer related questions.

Discussion about my current role at the office.

Round 3: Basic questions on networking.

OS questions: System call? Static/dynamic linking? Virtual memory? Process vs. Threads? Deadlock cases? How to handle shared data between threads?

Questions on college projects.

System design: Design a system to convert long URLs into short URLs. Need to handle insert/search and devise an algorithm for unique short URLs for all long URLs.

Buggy code snippet: Identify issues and suggest solutions.

Linked list: Handle insert/delete/get for all data types (int/char/struct) using a single linked list structure.

Design your own library to handle dynamic memory allocation/deallocation. What data structure would you maintain this information with?